An ATM is an electronic device that allows banking customers to carry out financial transactions without the need for a human teller. For example, customers may use an ATM to access their bank accounts, deposit, withdraw, or transfer funds, check account balances, or dispense items of value. Generally, to use an ATM, the customer may insert a banking card containing magnetic stripe information into the ATM's card reader, and authenticate the card by entering a personal identification number (PIN). After the card has been read and authenticated, the customer can carry out various financial transactions.
While ATMs are convenient, their use can also be risky. Thieves have been known to attach devices known as “skimmers” on or adjacent to ATMs to capture the card information and PINs entered by the customer. These skimmers can remain on the ATM for an extended period of time prior to detection, and are sometimes constructed to match the visual appearance of the ATM's card reader. Thus, the customer is unable to determine whether the device is a skimmer or part of the ATM itself. Skimmers may also be used in conjunction with video cameras designed to record the customers' PINs or other entered account data. The video cameras are often hidden and/or designed to blend in with the appearance ATM so that a customer is unable to detect anything out of the ordinary. Skimmers may also be used in conjunction with a keypad overlay placed on top of the ATM's keypad. The keypad overlay contains circuitry that records the numbers that customers type as they enter their PINs. The keypad overlays, however, are typically designed to blend in with the appearance of the ATM, making them difficult for customers to detect.
To combat these unauthorized devices, bank employees often conduct periodic visual reviews of the ATM's appearance. However, these visual reviews are error prone (sometimes the skimmer, video camera, and/or keypad overlay is not found), labor intensive, time consuming, and expensive. Accordingly, a need exists to detect these unauthorized devices quickly and inexpensively and thus mitigate the risk of the compromise of a customer's card data.